java-programmer >>Java GUI lag during window resizing on laptop

Java GUI lag during window resizing on laptop

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    Are file writing operations atomic ? ie when you write to a file,
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    Has anyone done anything similar b4? if so how did you handle this
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  - comp.lang.java.{help,programmer} - what they're for (mini-FAQ 2004-10-08)Last-Modified: Fri Oct 8 11:38:42 2004 by David Alex Lamb
    Archive-name: computer-lang/java/help/minifaq
    Posting-Frequency: every 4 days
    
    Before posting read Jon Skeet's "How to get answers on the comp.lang.java.*
    newsgroups" at http://www.pobox.com/~skeet/java/newsgroups.html
    
    Java FAQs and advice:
    - Java FAQ (Andrew Thompson) http://www.physci.org/codes/javafaq.jsp
    including his list of other FAQs http://www.physci.org/codes/javafaq.jsp#faq
    - Java/Javascript/Powerbuilder HOWTO (Real Gagnon)
    http://www.rgagnon.com/howto.html
    - Java Glossary (Roedy Green) http://www.mindprod.com/jgloss.html
    - jGuru jFAQs (John Zukowski) http://www.jguru.com/jguru/faq/
    - Focus on Java (John Zukowski) http://java.about.com/
    - Java Q&A (David Reilly) http://www.davidreilly.com/jcb/faq/
    - Java GUI FAQ (Thomas Weidenfeller) http://www.physci.org/guifaq.jsp
    
    comp.lang.java.help Set-up problems, catch-all first aid.
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    --
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    http: http://netnet.net/~farmer/index.html
    
    With all of thy getting, get understanding!
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    // TODO Auto-generated method stub
    byte[] re = null;
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    if (key.length != 8){
    throw new DesException("Invalid Key!!!");
    }
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    Cipher des = Cipher.getInstance("DES");
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    re = des.doFinal(data);
    
    des.init(Cipher.DECRYPT_MODE, desKey);
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    return re;
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    Cheers, Dani
    
    _______________________________________________
    email***@***.com mailing list
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- 14
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    Should I find a new Java job?

Author

Message

M. P.

Posted: 2006-3-10 19:49:00

Top

java-programmer, Java GUI lag during window resizing on laptop I was messing around with a Java application I developed on my latop
and noticed something interesting. There seems to be lag with resizing
the windows and resizing the panels via the dividers. BUT this lag
only occurs when my laptop runs on the battery, or, rather, you don't
see this when it is connected to an AC power source.

This also occurs in some other Java applications I downloaded and
tested. But there are others that do not have this behavior.

I am not sure why this happens. But what I do know is that some laptop
manufacturers reduce power consumption by limiting hardware (and
software) factors, including slowing the CPU clock -- not sure if that
is the cause.

Not sure if anyone can give any input to what might be causing this --
an is there a way to rewrite/manupilate my code so that it does not
happen?

VisionSet

Posted: 2006-3-11 3:01:00

Top

java-programmer >> Java GUI lag during window resizing on laptop
"M. P." <email***@***.com> wrote in message
news:email***@***.com...

> I am not sure why this happens. But what I do know is that some laptop
> manufacturers reduce power consumption by limiting hardware (and
> software) factors, including slowing the CPU clock -- not sure if that
> is the cause.

Probably, Swing speed is noticibly slower below about 700mhz cpu
I've been on that divide for 5 years!

>
> Not sure if anyone can give any input to what might be causing this --
> an is there a way to rewrite/manupilate my code so that it does not
> happen?
>

Don't use Swing frame decorations
More drastically use AWT

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    >
    > ------
    > ACGNJ Java Users Group
    > http://www.javasig.org/
    >
- 8
  - AWT/Swing layout behavior?I am having trouble figuring out the right way to use the GridBagLayout
    class.
    
    I have some sample code (see below) that I _expected_ would take the two
    components added to the frame and always make them the same size, arranged
    vertically.
    
    What happens instead is that when one of the two components is a Panel or
    JPanel (and possibly other container types...those are the two I tested),
    if that component contains another component, it takes up more than half
    of the frame.
    
    Reading the documentation, I am under the impression that the
    GridBagLayout class automatically allocates the dimensions of a given
    component according to the weight assigned to it in the GridBagConstraints
    class set for the component. Thus, since these two components have the
    same weights, they should always be equally sized. But for some reason,
    having the container actually contain something affects this.
    
    The sample code only adds one item, and the difference in size is
    noticeable but not very large. However, this came up in a more complex
    situation, where a larger number of controls are added. In that case, the
    size difference is proportionally larger as well, resulting in effective
    relative weights more like 3 or 4 to 1.
    
    Is there a way to get the GridBagLayout class, or some other built-in
    LayoutManager, to do this sort of auto-sizing where the relative weights
    will always actually stay equal?
    
    Thanks!
    Pete
    
    p.s. Something I ran into while putting the sample code together is that
    sometimes when I'd run the code, the button would not show up. It'd be
    briefly visible, and it would show up again once the window is resized.
    But to start with, it's not visible. Is there some basic flaw in the way
    I'm creating this UI that is leading to this erratic behavior? Or am I
    just looking at some sort of run-time bug?
    
    import java.awt.*;
    import javax.swing.*;
    import javax.swing.border.*;
    
    public class TestPanel
    {
    
    /**
    * @param args
    */
    public static void main(String[] args)
    {
    Frame frame = new Frame("TestPanel");
    GridBagLayout grid = new GridBagLayout();
    GridBagConstraints constraints = new GridBagConstraints();
    JPanel panel;
    
    frame.setLayout(grid);
    
    constraints.fill = GridBagConstraints.BOTH;
    constraints.gridwidth = GridBagConstraints.REMAINDER;
    constraints.weightx = 1;
    constraints.weighty = 1;
    
    panel = new JPanel();
    panel.setBorder(new LineBorder(Color.BLACK));
    panel.add(new Button("Test"));
    frame.add(panel);
    grid.setConstraints(panel, constraints);
    
    panel = new JPanel();
    panel.setBorder(new LineBorder(Color.BLACK));
    frame.add(panel);
    grid.setConstraints(panel, constraints);
    
    frame.setSize(240, 480);
    frame.setVisible(true);
    }
    }
- 9
  - findind how many characters in some amount of pixels.Hi ,
    
    I am working on JTable data printing.In that i have some problem.If
    anyone can help me,please help me.
    
    how to find the no.of characters in some amount of pixels ?
    
    TableColumn tk = colModel.getColumn(nCol);
    int width_1 = tk.getWidth();
    finding string width using
    fontMetric.stringWidth(string);
    
    how to substring the string based on coloum width and string width
    which will fit into the particular column.
    
    If anybody knows solution for this problem, Please give me the reply.
    
    thanking you
    Bharath
- 10
  - New Software Development Articles DirectoryA new links directory of articles related to software development is
    "under construction" on http://www.softdevarticles.com/
    
    Please feel free to use it in you next research and to contribute with
    your articles on Java.
- 11
  - Serialize Applet to a web server via Servlet ProblemHi,
    
    I try to Serialise an Applet on my WebServer, i convert Object to
    ByteArray, before sending it to webserver.
    There is 2050 bytes in byte array on my applet before sending it, and
    2062 bytes in byte array on tomcat !
    
    Where is my mistake ?
    Regards
    Philippe
    
    Applet
    void WriteApplet(String filename)
    {
    ObjectOutputStream out;
    System.out.println("Debut Test WRITE APPLET...");
    
    //Serialisation de la frame
    try
    {
    String m_URL=new
    String("http://172.16.0.101:8080/test/servlet/servletgraph.XXServlet");
    String string4=m_URL;
    System.out.println("w01 "+string4);
    
    URL u=new URL(string4);
    
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    ObjectOutputStream oos = new ObjectOutputStream(baos);
    oos.writeObject(this);
    oos.flush();
    oos.close();
    byte b[] = baos.toByteArray();
    
    HttpURLConnection urlc = (java.net.HttpURLConnection)
    u.openConnection();
    // Set the Post (true) or Get (false) method.
    urlc.setDoOutput(true);
    urlc.setDoInput(true);
    urlc.setUseCaches(false);
    urlc.setAllowUserInteraction(false);
    
    urlc.setRequestProperty("Content-Type",
    "application/octet-stream");
    
    String lengthString = String.valueOf(baos.size());
    urlc.setRequestProperty("Content-Length", lengthString);
    System.out.println("Object is avant ecriture " + lengthString + "
    bytes");
    
    out = new ObjectOutputStream(urlc.getOutputStream());
    out.write(b);
    
    if (urlc.getResponseCode() != HttpURLConnection.HTTP_OK) {
    System.out.println("Error...");
    } else {
    System.out.println("I have now access to the stream...");
    // blaha balaaha blaahahaha
    }
    
    out.flush();
    out.close();
    System.out.println("Fin Test WRITE APPLET...");
    }
    catch (IOException ioe) {
    System.err.println(ioe);
    ioe.printStackTrace();
    }
    }
    
    -------------------------------------------------------------------------
    
    Servlet
    public void doPost(HttpServletRequest req, HttpServletResponse resp)
    throws ServletException, IOException
    {
    System.out.println("XXServlet doPost X1 "+new Date());
    boolean debug=true;
    
    InputStream in = req.getInputStream();
    byte[] bufimage=null;
    bufimage = new byte[4 * 1024]; // 4K buffer
    int len;
    RandomAccessFile f = new
    java.io.RandomAccessFile(req.getRealPath("/")+"xxservlet", "rw");
    int size = req.getIntHeader("content-length");
    bufimage = new byte[size]; // 4K buffer
    if(debug) System.out.println("XXServlet bytearray02 "+size);
    int nb=0;
    while ((len = in.read(bufimage, 0, bufimage.length)) != -1)
    {
    if(debug) System.out.println("XXServlet bytearray03
    content-length "+len);
    f.write(bufimage, 0, len); //Fichier
    nb=+len;
    
    }
    if(debug) System.out.println("XXServlet bytearray05 "+nb);
    
    f.close();
    
    if(debug) System.out.println("XXServlet write04 ");
    
    }
    }
- 12
  - UnixODBCconfig-root wont startI have UnixODBC installed on my Mandriva 2008, of late I cannot seem
    to start ODBCconfig-root, when i run it via terminal i get the root
    pass dialog but then it dies giving me this error...
    
    ODBCConfig-root: symbol lookup error: ODBCConfig-root: undefined
    symbol: ODBCINSTSQLManageDataSources
    
    Can someone help me through this?
- 13
  - No window control in an Application WindowHi,
    
    After following a JFACE eclipse example, i created a new class that
    extends ApplicationWindow that create a nice window with tool bar, menu
    bar and status bar. That's great.... but my window doesn't have window
    controls to minimize or iconify it, only the quit element (the cross)!
    Does anybody know which attribute i have to set to have window
    controls?
    
    Thx
    
    0o.
- 14
  - How about to lauch a new thread in a constructor?I read one piece of code written by somebody and behold interesting
    class as below:
    
    class SomeFramework {
    public SomeFramework() {
    ...
    DameonThread dameon = new DameonThread();
    dameon.start();
    }
    
    private doSomething() {
    ...
    }
    
    private class DameonThread extends Thread {
    public void run() {
    ...
    doSomething();
    ...
    }
    }
    }
    
    As you can see, in the constructor of SomeFramework, one thread is
    launched and that thread will call the SomeFramework instance's private
    method. Perhaps the author design this code to make the client code
    easy. The client just call "new SomeFramework()" and everything is done.
    No need to coding like
    SomeFramwork framework = new SomeFramework();
    framework.lauch();
    
    However, the problem is that it is possible that when the dameon is
    started, CPU will go into run and call doSomething() of the instance of
    SomeFramework. But, at that time, the constructor is not returned. Is it
    reasonable to call a method of a un-instanstized object? Curiously, this
    code works well all the time. Luckily, before dameon is started, all
    member variables are instantized in constructor, but I really think this
    code is ugly and should be avoided.
- 15
  - metadata and stored proceduresHi everybody,
    
    I use a CallableStatement to run my stored procedure, and I would like
    to retrive the columns name of the result.
    So I try to use the getMetaData method of my CallableStatement, but it
    returns me null futhermore than le callablestatement returns data.
    How can I do to retrieve my columns names ?
    Thanks
    
    Thomas